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OBJECTIVE: The aim of this study was to investigate whether there is an association between hair cortisol concentrations and acute stress symptoms in family members of critically ill patients. METHODS: A cross-sectional study was conducted in an adult intensive care unit of a tertiary hospital in Porto Alegre, Brazil, from August 2021 to February 2022. Family members of intensive care unit patients admitted for more than 10 days were approached for enrollment. We collected sociodemographic data and assessed resilience, religiosity, and symptoms of acute stress among family members. Samples of family members' hair were collected shortly after the interview to measure the hair cortisol concentration. RESULTS: A total of 110 family members were included in this study. Eighty-eight (80.0%) family members presented with symptoms of acute stress. The median hair cortisol concentration was 2.37pg/mg (1.16 - 5.06pg/mg). There was no significant difference in hair cortisol concentration between family members with and without acute stress symptoms (p = 0.419). According to the multivariate analysis, only the fact that the patient was alert at the time of the family member's interview was significantly associated with the prevalence of acute stress symptoms in the family member. CONCLUSION: We did not find an association between the hair cortisol concentration of family members in hair segments in the months prior to admission to the intensive care unit and the occurrence of acute stress symptoms.
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Enfermedad Crítica , Familia , Cabello , Hidrocortisona , Unidades de Cuidados Intensivos , Estrés Psicológico , Humanos , Hidrocortisona/análisis , Hidrocortisona/metabolismo , Estudios Transversales , Masculino , Femenino , Cabello/química , Persona de Mediana Edad , Brasil/epidemiología , Familia/psicología , Estrés Psicológico/metabolismo , Estrés Psicológico/epidemiología , Estrés Psicológico/diagnóstico , Adulto , AncianoRESUMEN
ABSTRACT BACKGROUND AND OBJECTIVES: Lumbar disorders, which contribute to significant workplace absenteeism and chronic disability, are associated with a considerable financial and social burden. Although a conservative approach provides satisfactory pain relief, biomechanical improvement and is associated with a low risk of adverse effects, there is lack of consensus in the literature regarding the best therapeutic strategy in such cases. METHODS: This retrospective longitudinal study used secondary data from the institutional medical records of patients who completed a multidisciplinary program for the treatment of low back pain between 2019 and 2021. Data regarding pain levels and motor skills were obtained from patients who completed the care program at a private hospital in Bento Gonçalves, RS. The following step-wise treatment algorithm was used: evaluation by a specialist physician for the etiological diagnosis of pain, pharmacological management and dry needling, followed by standard rehabilitation intervention performed by the physiotherapy team and exercises by the physical education team. The visual analogue scale (VAS) was used to measure pain at the start and at the completion of the intervention, and the Oswestry Disability Index (ODI) was used to measure motor skills at the start and at 6 and 12 months following the multiprofessional intervention for rehabilitation. RESULTS: A reduction in pain and motor disability in patients who completed all stages of the treatment program was observed. Pain by the VAS presented the following scores: baseline 7 [5-8] and after treatment 2 [0-4]; and the scores of the ODI were: at baseline 0.34 [0.26 - 0.40], at 6 months 0.16 [0.08 - 0.26] and after treatment 0.12 [0.04 - 0.21]. CONCLUSION: The treatment program reduced the pain and disability associated with low back pain and can serve as the basis for further studies carried out to confirm the effectiveness of this intervention.
RESUMO JUSTIFICATIVA E OBJETIVOS: As doenças lombares, que contribuem para um absenteísmo significativo no local de trabalho e para a incapacidade crônica, estão associadas a um encargo financeiro e social considerável. Embora a abordagem conservadora proporcione alívio satisfatório da dor, melhore a biomecânica e esteja associada a baixo risco de efeitos adversos, não há consenso na literatura sobre a melhor estratégia terapêutica nesses casos. MÉTODOS: Neste estudo longitudinal retrospectivo, foram utilizados dados secundários dos prontuários médicos institucionais de pacientes que completaram um programa multidisciplinar para tratamento de dor lombar entre 2019 e 2021. Dados sobre níveis de dor e habilidades motoras foram obtidos de pacientes que completaram o programa assistencial de um hospital privado de Bento Gonçalves, RS. Foi utilizado o seguinte tratamento passo a passo: avaliação por médico especialista para diagnóstico etiológico da dor, manejo farmacológico e agulhamento a seco, seguido de intervenção de reabilitação padrão realizada pela equipe de fisioterapia e exercícios pela equipe de educação física. A escala analógica visual (EAV) foi utilizada para medir a dor no início e após a conclusão da intervenção, e o Índice de Incapacidade de Oswestry (ODI) foi usado para medir as habilidades motoras no início e aos 6 e 12 meses após a intervenção multiprofissional para reabilitação. RESULTADOS: Observou-se redução na dor e na incapacidade motora em pacientes que completaram todas as etapas do programa de tratamento. A intensidade da dor medida pela EAV apresentou as seguintes pontuações: basal 7 [5-8] e após tratamento 2 [0-4]; enquanto o ODI apresentou as pontuações: basal 0,34 [0,26 - 0,40], até 6 meses 0,16 [0,08 - 0,26] e após o tratamento 0,12 [0,04 - 0,21]. CONCLUSÃO: O programa de tratamento reduziu a dor e a incapacidade associadas à dor lombar e pode servir de base para novos estudos realizados para confirmar a eficácia desta intervenção.
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Introduction: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, resulting in a range of clinical manifestations and outcomes. Laboratory and immunological alterations have been considered as potential markers of disease severity and clinical evolution. Type I interferons (IFN-I), mainly represented by IFN-α and ß, are a group of cytokines with an important function in antiviral responses and have played a complex role in COVID-19. Some studies have demonstrated that IFN-I levels and interferon response is elevated in mild cases, while other studies have noted this in severe cases. The involvement of IFN-I on the pathogenesis and outcomes of SARS-CoV-2 infection remains unclear. In this study, we summarize the available evidence of the association of plasma protein levels of type I IFN with the severity of COVID-19. Methods: The PRISMA checklist guided the reporting of the data. A systematic search of the MEDLINE (PubMed), EMBASE, and Web of Science databases was performed up to March of 2021, looking for articles that evaluated plasma protein levels of IFN-I in mild, severe, or critical COVID-19 patients. Comparative meta-analyses with random effects were performed to compare the standardized mean differences in plasma protein levels of IFN-I of mild versus severe and mild versus critical patients. Meta-regressions were performed to test the moderating role of age, sex, time that the IFN-I was measured, and limit of detection of the assay used in the difference between the means. Results: There was no significant difference in plasma levels of IFN-α when comparing between mild and severe patients (SMD = -0.236, 95% CI -0.645 to 0.173, p = 0.258, I2 = 82.11), nor when comparing between patients mild and critical (SMD = 0.203, 95% CI -0.363 to 0.770, p = 0.481, I2 = 64.06). However, there was a significant difference between healthy individuals and patients with mild disease (SMD = 0.447, 95% CI 0.085 to 0.810, p = 0.016, I2 = 62.89). Conclusions: Peripheral IFN-α cannot be used as a severity marker as it does not determine the clinical status presented by COVID-19 patients.
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Biomarcadores/sangre , COVID-19/diagnóstico , Interferón Tipo I/sangre , SARS-CoV-2/fisiología , Progresión de la Enfermedad , Humanos , Índice de Severidad de la EnfermedadRESUMEN
Abstract Breast cancer is one of the leading types of cancer worldwide, and the search for new treatment options are crucial. Nonsteroidal anti-inflammatory drugs (NSAIDs) -specially ibuprofen and diclofenac-, have shown antitumoral effect against several types of cancer. The synthesis of organometallic compounds has shown significant improvements in pharmacological properties and efficacy of organic molecules. Two zinc II ternary complexes containing the NSAIDs diclofenac and ibuprofen and nicotinamide neutral linker (Nic) were obtained by the two-step solvent metalligand complexation method. The compounds Zn2(Diclof)4(Nic)2 (complex 1) and Zn2(Ibup)4(Nic)2 (complex 2) were tested in breast cancer cell lines (4T1, MCF-7 and MDA-MB-231) to evaluate their cytotoxicity, comparing to ibuprofen and diclofenac as controls. We found that both complex 1 and 2 exerted more than 60% reduction in 4T1 viability at 250µM, and complex 2 decreased cell viability at 250 µM and 137.5 µM in MCF-7 (34.35% and 26.42% reduction, respectively) and in MDA-MB-231 (57.2% and 22.88% reduction, respectively), all compared to controls. Complex 1 was selective only in MCF-7, and complex 2 was selective in both MCF-7 and MDA-MB-231. In summary, our data showed that the cytotoxic effect of complex 1 and 2 is increased comparing to their original NSAID in different breast cancer cell lines, highlighting their potential anti-tumoral activity.
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This study investigated the effects of P/Q- and N-type voltage-gated calcium channel (VGCC) blockers derived from P. nigriventer in glioma progression, by means of in vitro and in vivo experiments. Glioma cells M059J, U-138MG and U-251MG were used to evaluate the antiproliferative effects of P/Q- and N-type VGCC inhibitors PhTx3-3 and Phα1ß from P. nigriventer (0.3-100 pM), in comparison to MVIIC and MVIIA from C. magus (0.3-100 pM), respectively. The toxins were also analyzed in a glioma model induced by implantation of GL261 mouse cells. PhTx3-3, Phα1ß and MVIIA displayed significant inhibitory effects on the proliferation and viability of all tested glioma cell lines, and evoked cell death mainly with apoptosis characteristics, as indicated by Annexin V/propidium iodide (PI) positivity. The antiproliferative effects of toxins were confirmed by flow cytometry using Ki67 staining. None of the tested toxins altered the proliferation rates of the N9 non-tumor glial cell line. Noteworthy, the administration of the preferential N-type VGCC inhibitors, Phα1ß (50 pmol/site; i.c.v.), its recombinant form CTK 01512-2 (50 pmol/site; i.c.v. and i.t.), or MVIIA (10 pmol/site; i.c.v.) caused significant reductions of tumor areas in vivo. N-type VGCC inhibition by Phα1ß, CTK 01512-2, and MVIIA led to a marked increase of GFAP-activated astrocytes, and Iba-1-positive microglia, in the peritumoral region, which might explain, at least in part, the inhibitory effects of the toxins in tumor development. This study provides novel evidence on the potential effects of P. nigriventer-derived P/Q-, and mainly, N-type VGCC inhibitors, in glioma progression.
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Bloqueadores de los Canales de Calcio/farmacología , Neuropéptidos/farmacología , Venenos de Araña/farmacología , Arañas/química , Animales , Canales de Calcio Tipo N/efectos de los fármacos , Canales de Calcio Tipo N/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Glioma/tratamiento farmacológico , Humanos , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Elevated plasma levels of homocysteine (Hcy) are associated with the development of coronary artery disease (CAD), peripheral vascular disease, and atherosclerosis. Hyperhomocysteinemia is likely related to the enhanced production of pro-inflammatory cytokines including IL-1ß. However, the mechanisms underlying the effects of Hcy in immune cells are not completely understood. Recent studies have established a link between macrophage accumulation, cytokine IL-1ß, and the advance of vascular diseases. The purpose of the present study is to investigate the effects of Hcy on IL-1ß secretion by murine macrophages. Hcy (100 µM) increases IL-1ß synthesis via enhancement of P2X7 expression and NF-ĸB and ERK activation in murine macrophages. In addition, the antioxidant agent N-acetylcysteine (NAC) reduces NF-κB activation, ERK phosphorylation, and IL-1ß production in Hcy-exposed macrophages, indicating the importance of ROS in this pro-inflammatory process. In summary, our results show that Hcy may be involved in the synthesis and secretion of IL-1ß via NF-ĸB, ERK, and P2X7 stimulation in murine macrophages.
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Homocisteína/toxicidad , Hiperhomocisteinemia/metabolismo , Interleucina-1beta/biosíntesis , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/metabolismo , FN-kappa B/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Acetilcisteína/farmacología , Animales , Antioxidantes/farmacología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/genéticaRESUMEN
Macrophages are involved in cancer progression. M1 macrophages have an antitumor effect, whereas M2 phenotype are associated with tumor growth. The progression of gliomas involves the participation of an inflammatory microenvironment. Adenosine triphosphate (ATP) can act as pro-inflammatory signal, whereas adenosine has opposite properties. The biological effects of extracellular nucleotides/nucleosides mediated by purinergic receptors are controlled by ectonucleotidases. In the present work, we evaluated whether glioma-conditioned medium (GL-CM) modulates macrophage differentiation and the participation of ATP and adenosine in the release of pro-and anti-inflammatory cytokines by these cells. The results show that macrophages exposed to GL-CM were modulated to an M2-like phenotype. HPLC analysis of GL-CM demonstrated the presence of significant amounts of ATP and its metabolites. Macrophages exposed to GL-CM presented decreased ATP and AMP hydrolysis and increased IL-10 and MCP-1 secretion, effects that were diminished by P1 or P2 antagonists. GL-CM did not alter the release of IL-6 by macrophages, although treatment with ATP promoted an increase in the release of IL-6, which was prevented by a P2X7 antagonist. In summary, we found that A2A and P2X7 activation is necessary for IL-10, MCP-1, and IL-6 release by macrophages exposed to GL-CM, which, in turn, modulates the macrophages to M2-phenotype. The present study establishes a relationship between M2-like polarization, cytokine release and purinergic receptor activation in macrophages exposed to GL-CM. Therefore, the data presented herein contributes to advancing in the field of cancer-related inflammation and point specific purinergic receptors as targets for modulation of the phenotype of glioma-associated macrophages.
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Quimiocina CCL2/metabolismo , Glioma/metabolismo , Interleucina-10/metabolismo , Macrófagos/metabolismo , Fragmentos de Péptidos/metabolismo , Receptores Purinérgicos/metabolismo , Adenosina/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Línea Celular Tumoral , Medios de Cultivo Condicionados/metabolismo , Interleucina-6/metabolismo , Masculino , Ratones , Receptor de Adenosina A2A/metabolismo , Receptores Purinérgicos P2X7/metabolismoRESUMEN
Gliomas are the most common malignant brain tumors in adults. Bradykinin (BK) displays an important role in cancer, although the exact role of kinin receptors in the glioma biology remains unclear. This study investigated the role of kinin B1 and B2 receptors (B1R and B2R) on cell proliferation in human glioblastoma cell lineages. The mRNA expression of B1R and B2R was verified by RT-qPCR, whereas the effects of kinin agonists (des-Arg(9)-BK and BK) were analyzed by cell counting, MTT assay and annexin-V/PI determination. The PI3K/Akt and ERK1/2 signaling activation was assessed by flow cytometry. Our results demonstrated that both human glioblastoma cell lines U-138MG and U-251MG express functional B1R and B2R. The proliferative effects induced by the incubation of des-Arg(9)-BK and BK are likely related to the activation of PI3K/Akt and ERK 1/2 pathways. Moreover, the pre-incubation of the selective PI3Kγ blocker AS252424 markedly prevented kinin-induced AKT phosphorylation. Noteworthy, the selective B1R and B2R antagonists SSR240612 and HOE-140 were able to induce cell death of either lineages, with mixed apoptosis/necrosis characteristics. Taken together, the present results show that activation of B1R and B2R might contribute to glioblastoma progression in vitro. Furthermore, PI3K/Akt and ERK 1/2 signaling may be a target for adjuvant treatment of glioblastoma with a possible impact on tumor proliferation.
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Proliferación Celular , Glioma/metabolismo , Glioma/patología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Bradiquinina B1/metabolismo , Receptor de Bradiquinina B2/metabolismo , Apoptosis , Western Blotting , Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Antagonistas del Receptor de Bradiquinina B1/farmacología , Antagonistas del Receptor de Bradiquinina B2/farmacología , Dioxoles/farmacología , Citometría de Flujo , Glioma/tratamiento farmacológico , Humanos , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Fosfatidilinositol 3-Quinasas/genética , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor de Bradiquinina B1/química , Receptor de Bradiquinina B1/genética , Receptor de Bradiquinina B2/química , Receptor de Bradiquinina B2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sulfonamidas/farmacología , Células Tumorales CultivadasRESUMEN
Increasing evidence points out that genetic alteration does not guarantee the development of a tumor and indicates that complex interactions of tumor cells with the microenvironment are fundamental to tumorigenesis. Among the pathological alterations that give tumor cells invasive potential, disruption of inflammatory response and the purinergic signaling are emerging as an important component of cancer progression. Nucleotide/nucleoside receptor-mediated cell communication is orchestrated by ectonucleotidases, which efficiently hydrolyze ATP, ADP, and AMP to adenosine. ATP can act as danger signaling whereas adenosine, acts as a negative feedback mechanism to limit inflammation. Many tumors exhibit alterations in ATP-metabolizing enzymes, which may contribute to the pathological events observed in solid cancer. In this paper, the main changes occurring in the expression and activity of ectonucleotidases in tumor cells as well as in tumor-associated immune cells are discussed. Furthermore, we focus on the understanding of the purinergic signaling primarily as exemplified by research done by the group on gliomas.
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Adenosina Trifosfatasas/metabolismo , Linfocitos/enzimología , Neoplasias/enzimología , Neoplasias/inmunología , Animales , Progresión de la Enfermedad , Humanos , Modelos Biológicos , Neoplasias/patologíaRESUMEN
Gliomas are the most lethal tumors of central nervous system. ATP is an important signaling molecule in CNS and it is a selective P2X7 purinergic receptor ligand at high concentrations. Herein, we investigated whether the activation of P2X7R might be implicated in death of a radiosensitive human glioma lineage. The effects of P2X7R agonists (ATP and BzATP) and irradiation (2 Gy) on glioma cells were analyzed by MTT assay and annexin-V/PI determination, whereas mRNA and protein P2X7R expression was assessed by qRT-PCR and flow cytometry, respectively. P2X7R pore formation was functionality examined by analyzing ethidium bromide uptake. The human glioma cells U-138 MG and U-251 MG were resistant to death when treated with either ATP (5 mM) or BzATP (100 µM), but the radiosensitive M059J glioma cells displayed a significant decrease of cell viability (32.4 ± 4.1 % and 25.6 ± 3.3 %, respectively). The M059J lineage expresses significantly higher mRNA P2X7R levels when compared to the U-138 MG and U-251 cell lines (0.40 ± 0.00; 0.28 ± 0.01, and 0.31 ± 0.01, respectively), and irradiation upregulated P2X7R expression (0.55 ± 0.08) in this lineage. Noteworthy, P2X7R protein doubled after irradiation on M059J lineage, and increased in 50 % and 42.6 % when comparing M059J-irradiated to irradiated U-138 MG and U-251 MG cells, respectively. Ethidium bromide uptake was significantly increased in 104 % and 77.8 % when comparing M059J to U-138 MG and U-251MG, respectively. Finally, the selective P2X7R antagonist A740003 significantly decreased the cell death caused by irradiation. We provide novel evidence indicating that M059J human glioma cell line is ATP-P2X7R sensitive, pointing out the relevance of the purinergic P2X7R on glioma radiosensitivity.
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Glioma/radioterapia , Receptores Purinérgicos P2X7/metabolismo , Adenosina Trifosfato/metabolismo , Muerte Celular/efectos de la radiación , Línea Celular Tumoral , Glioma/metabolismo , Humanos , Regulación hacia Arriba/efectos de la radiaciónRESUMEN
Macrophages are key elements in the inflammatory process, whereas depending on the micro-environmental stimulation they exhibit a pro-inflammatory (classical/M1) or an anti-inflammatory/reparatory (alternative/M2) phenotype. Extracellular ATP can act as a danger signal whereas adenosine generally serves as a negative feedback mechanism to limit inflammation. The local increase in nucleotides communication is controlled by ectonucleotidases, such as members of the ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) family and ecto-5'-nucleotidase/CD73 (ecto-5'-NT). In the present work we evaluated the presence of these enzymes in resident mice M1 (macrophages stimulated with LPS), and M2 (macrophages stimulated with IL-4) macrophages. Macrophages were collected by a lavage of the mice (6-8 weeks) peritoneal cavity and treated for 24 h with IL-4 (10 ng/mL) or LPS (10 ng/mL). Nitrite concentrations were measured using the Greiss reaction. Supernatants were harvested to determine cytokines and the ATPase, ADPase and AMPase activities were determined by the malachite green method and HPLC analysis. The expression of selected surface proteins was evaluated by flow cytometry. The results reveal that M1 macrophages presented a decreased ATP and AMP hydrolysis in agreement with a decrease in NTPDase1, -3 and ecto-5'-nucleotidase expression compared to M2. In contrast, M2 macrophages showed a higher ATP and AMP hydrolysis and increased NTPDase1, -3 and ecto-5'-nucleotidase expression compared to M1 macrophages. Therefore, macrophages of the M1 phenotype lead to an accumulation of ATP while macrophages of the M2 phenotype may rapidly convert ATP to adenosine. The results also showed that P1 and P2 purinoreceptors present the same mRNA profile in both phenotypes. In addition, M2 macrophages, which have a higher ATPase activity, were less sensitive to cell death. In conclusion, these changes in ectoenzyme activities might allow macrophages to adjust the outcome of the extracellular purinergic cascade in order to fine-tune their functions during the inflammatory set.
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5'-Nucleotidasa/análisis , Perfilación de la Expresión Génica , Activación de Macrófagos/genética , Pirofosfatasas/análisis , 5'-Nucleotidasa/genética , Adenosina/biosíntesis , Adenosina/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Ratones , Pirofosfatasas/genética , ARN Mensajero/análisis , Receptores Purinérgicos P1/genética , Receptores Purinérgicos P2/genéticaRESUMEN
BACKGROUND: Uterine cervical neoplasia is an important worldwide malignancy sometimes associated with thrombosis. Ectonucleotidases are membrane-bound enzymes which participate in thromboregulation by hydrolyzing adenine nucleotides in the extracellular medium. In this sense, we aimed to investigate their activity in patients with uterine cervical neoplasia. METHODS: We evaluated NTPDase and 5'-nucleotidase activities from patients previously treated for uterine cervical neoplasia with either conization or radiotherapy (RTX). These patients were divided into four groups: two conization groups (I and II) and two RTX groups (III and IV), which were further divided based on the amount of time that had passed since the conclusion of their treatment, where groups I and III were extended-remission-period groups (patients with 1 to 5 years elapsed after the conclusion of treatment), and groups II and IV were recently treated patients (treated up to three months before). RESULTS: For both conization and RTX groups, ATP and ADP hydrolysis decreased in the extended-remission groups when compared to the control and recently treated groups. On the other hand, AMP hydrolysis was decreased in all the treated groups (both conization and RTX) compared to the control. CD39 expression was decreased in extended-remission groups (I and III) when compared to the other groups. CONCLUSIONS: NTPDase protects against platelet aggregation and 5'-nucleotidase is more involved in the control of adenosine formation.
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Antígenos CD/sangre , Apirasa/sangre , Plaquetas/enzimología , Conización , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/cirugía , 5'-Nucleotidasa/sangre , Adenosina Difosfato/metabolismo , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Pruebas de Coagulación Sanguínea , Femenino , Humanos , Persona de Mediana Edad , Agregación Plaquetaria , Recuento de Plaquetas , Plasma Rico en Plaquetas , Neoplasias del Cuello Uterino/sangre , Neoplasias del Cuello Uterino/enzimología , Frotis VaginalRESUMEN
Hyperhomocysteinemia is an independent risk factor for atherothrombotic disease. Platelets play an important role in cardiovascular disease and release pro-aggregates mediators when activated, such as ADP, a physiological agonist involved in normal hemostasis and thrombosis. NTPDases and 5'-nucleotidase are ecto-enzymes that hydrolyze ATP, ADP and AMP to adenosine playing an important role on blood flow and thrombogenesis by regulating ADP catabolism. The aim of the present study was evaluate extracellular adenine nucleotide hydrolysis of rat platelets exposed to homocysteine in vitro and in vivo. In vitro homocysteine (Hcy) in the concentration range of 20 to 500 microM caused a significant decrease on ATP (around 30%) and ADP (around 45%) hydrolysis, respectively, while AMP hydrolysis was not altered. Hcy was not able to inhibit the hydrolysis of ATP and ADP catalyzed by purified apyrase at the same concentrations tested in vitro on platelets, suggesting an indirect effect. The inhibitory effect of Hcy on platelets was prevented by antioxidants agents in vitro and in vivo. Furthermore homocysteine treatment increased platelet aggregation induced by ADP. Based on the results presented herein, we propose that inhibition of extracellular ATP and ADP hydrolysis caused by homocysteine was probably due oxidative stress, since antioxidants prevented such effects. These findings may contribute to an increase platelet response to ADP and consequence development of thrombotic risk attributed to hyperhomocysteinemia.
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Nucleótidos de Adenina/metabolismo , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Homocisteína/farmacología , Adenosina Difosfato/metabolismo , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Apirasa/metabolismo , Plaquetas/enzimología , Catálisis , Relación Dosis-Respuesta a Droga , Espacio Extracelular/metabolismo , Hidrólisis/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Factores de TiempoRESUMEN
INTRODUCTION: The thrombogenic process that affects the hypertensive patient is associated with regulatory mechanisms present in the vascular endothelium. These mechanisms involve release of an endothelium-derived relaxing factor, ectonucleotidase activity and calcium ion concentration. METHODS: Interference with ENTPDase activity in platelets of hypertensive patients and healthy donors was evaluated for arginine, sodium nitroprusside, and hydralazine. In addition, the kinetic behavior of NTPDase was determined in the presence of the vasodilator that showed the greatest inhibitory influence. RESULTS: Vasodilators decreased NTPDase activity with ATP and ADP as substrates. In controls, hydrolysis was increased in the presence of arginine. Captopril did not affect enzyme activities. The dose response for increasing sodium nitroprusside was biphasic. Kinetic behavior studies were estimated in the presence of sodium nitroprusside, which caused a mixed inhibition. The K(m) values increased and V(max) decreased with increasing sodium nitroprusside concentrations. The IC(50) and K(i) values indicated that the vasodilator was a strong NTPDase inhibitor when tested for the control and hypertensive group, using ATP and ADP as substrate, respectively. CONCLUSION: It is postulated that there was an interaction between vasodilators, NO donors and inhibition of NTPDase.
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Adenosina Trifosfatasas/sangre , Hipertensión/tratamiento farmacológico , Hipertensión/enzimología , Vasodilatadores/administración & dosificación , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
The activity of the enzymes NTPDase and 5'-nucleotidase was studied in both diabetes mellitus and an associated model of iron-overload. Rats were divided in five groups: citrate (CC), saline (S), diabetic (D), iron-overload (IO), and diabetic iron-overload (DIO). Diabetes was induced with alloxan (150 mg/kg), and iron-overload was induced with iron-dextran (10 intramuscular applications of +/-80 mg/kg). The enzymatic activities were evaluated in the platelets. The results demonstrated an increase in the activity of NTPDase with substrates ATP and ADP (60% and 120%, respectively; P<0.001), and 5'-nucleotidase (60%, P<0.001). This increase was more intense in the IO and DIO groups. The results obtained in vitro showed an activation in ATP, ADP, and AMP hydrolysis between 1 microM and 1,000 microM ferric nitrate concentrations, being more pronounced at 100 microM and decreasing at 1,000 microM. We concluded that diabetes mellitus in association with iron-overload increased the hydrolysis of adenine nucleotides in platelets, contributing to the abnormalities found in these pathological conditions.
Asunto(s)
5'-Nucleotidasa/metabolismo , Antígenos CD/metabolismo , Apirasa/metabolismo , Diabetes Mellitus Experimental/enzimología , Sobrecarga de Hierro/enzimología , Nucleótidos de Adenina/metabolismo , Adulto , Animales , Glucemia/análisis , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Diabetes Mellitus Experimental/inducido químicamente , Modelos Animales de Enfermedad , Compuestos Férricos/farmacología , Hematócrito , Hemoglobinas/análisis , Humanos , Hidrólisis/efectos de los fármacos , Hierro/sangre , Sobrecarga de Hierro/inducido químicamente , Masculino , Nitratos/farmacología , Ratas , Ratas WistarRESUMEN
BACKGROUND: Cervical cancer is a major cause of morbidity among women. We investigated the treatment effect on oxidative status from patients submitted to radiotherapy or conization surgery to high-grade SIL (squamous intraepithelial lesion) treatment, and oxidative profile from patients newly diagnosed for uterine cervix cancer, without treatment. METHODS: We determined the catalase activity in blood, reduced glutathione (GSH) in plasma, TBARS and protein carbonyl content from serum samples of the patients. RESULTS: The catalase activity, GSH levels, TBARS and protein carbonyl content had no statistical differences related to the controls, neither when the 2 treatments were compared, possibly because the antioxidant defense may be acting in the first period of the neoplasic transformation, and maybe indicating a possible arrest of the tumor cells caused by the efficiency of the treatments. In the non-treated patients, TBARS and protein carbonyl contents, GSH levels and catalase activity were shown to be increased comparing with the treated patients and compared with the controls indicating an tumor effect on oxidative profile, and the antioxidant activity been increased in the beginning of the tumor development. CONCLUSIONS: We suggest that the treatments were efficient in arrest of the tumor.